grass field practice

SixPapaCharlie

SixPapaCharlie

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Today I got a wild hair and decided to go to a grass field and practice.
For the locals it was Cedar mills which is very well cared for and not soft at all.

I have gone there twice before but never just gone out and spent some time practicing.

Question. On grass do you find it takes significantly more distance to get up to speed?

My wheels are very small which may or may not play a role.
I am holding back pressure and a couple times, the plane got off way to early and came back down even when I push the nose down to stay in ground effect.

Now obviously I was able to get off every time but it was ugly and scary. This field ends at the edge of a lake.

I am not sure if it is a mental thing because I am seeing the water approach but on pavement, I feel like my airspeed gets up to 70 pretty quick and as I climb, I accelerate to 80 during the pitch.

Today I felt like 60 was never going to get there and I am barely able to get to 70ks until I am above the treeline. Airspeed just hangs there a little below 70.

I need to go practice soft field technique at my home field with known points (500 ft, 1000 ft, 1500ft, etc) and get a better gauge of where I am rotating.

It may all be mental. Home field is 8k feet and this grass strip is 3k
Prior home field for me was 3800 and I never felt this issue but I was never looking at water.


So I guess the question is will the grass create a noticeable delay in getting up to speed.

Also does being below the treeline (no head wind) contribute to my airspeed being lower?


Thanks in advance!
 
Grass is fun huh!

Rule of thumb dry grass add 25% to your t/o distance, wet grass 30%

I like using the 70/50 rule, half down the runway I'm at 70% t/o speed or abort.
 
[nit]Runway length at DTO is 7002'[/nit]

Are you doing this from a rolling or a standing start?

If you like, we can out together this week and review technique.

Oh, 55WB will spoil you to grass ops. The Skylane will get you off that strip in a hurry!
 
You found out that grass does indeed have more drag than flat hard asphalt.
There's a big difference between short dry grass and long wet grass, any combination of those are different from each other. Just because it's a grass strip doesn't mean it's soft too. Conditions at grass strips can change from day to day, not so much on asphalt. I would guess that most of your strips in TX are very dry this time of year, unless there's been a recent thunderstorm. The worst for drag is long wet grass on a soft field.
I guess that 3000' does look pretty short to you, and it should be adequate for most planes on most days. Look out for those 95-100 degree days you guys have, check DA and performance charts, and leave your self a good margin for less than perfect flying skills.

It sounds like you're doing a soft field TO and settling back on the grass after liftoff. It takes a fine touch to liftoff and stay in ground effect and let the plane accelerate to climb speed all the while not letting it settle back on the grass. Practice it, it's all about attitude flying and feel.
I don't know what you're flying and I don't think it's one of these planes, but, some planes are not very good off pavement, like the Varieze's, Sonerai's, the small wheels are obviously part of the problem.
 
AggieMike88 said:
[nit]Runway length at DTO is 7002'[/nit]

Are you doing this from a rolling or a standing start?

If you like, we can out together this week and review technique.

Oh, 55WB will spoil you to grass ops. The Skylane will get you off that strip in a hurry!
Click to expand...

Rolling start.
I am sure the 182 will. I flew in one yesterday @GLE and I realized just how much runway I eat in the TB9. That 182 was up so quick. I think I recall the same thing from the Borger flight.

Let me check my schedule and if not this week, I can probably do next week.
 
champ driver said:
You found out that grass does indeed have more drag than flat hard asphalt.
There's a big difference between short dry grass and long wet grass, any combination of those are different from each other. Just because it's a grass strip doesn't mean it's soft too. Conditions at grass strips can change from day to day, not so much on asphalt. I would guess that most of your strips in TX are very dry this time of year, unless there's been a recent thunderstorm. The worst for drag is long wet grass on a soft field.
I guess that 3000' does look pretty short to you, and it should be adequate for most planes on most days. Look out for those 95-100 degree days you guys have, check DA and performance charts, and leave your self a good margin for less than perfect flying skills.

It sounds like you're doing a soft field TO and settling back on the grass after liftoff. It takes a fine touch to liftoff and stay in ground effect and let the plane accelerate to climb speed all the while not letting it settle back on the grass. Practice it, it's all about attitude flying and feel.
I don't know what you're flying and I don't think it's one of these planes, but, some planes are not very good off pavement, like the Varieze's, Sonerai's, the small wheels are obviously part of the problem.
Click to expand...

Yes, very dry field yesterday and the grass is kept very short so I believe it is optimal place to start working on this stuff.
 
SixPapaCharlie said:
Yes, very dry field yesterday and the grass is kept very short so I believe it is optimal place to start working on this stuff.
Click to expand...

So how big were the cracks in the ground?

I'll never forget landing at Dallas South (T13) a few years back for fuel. It was the middle of summer and extremely dry (by Missouri standards anyway). I couldn't believe the size of the cracks in the ground. Many of them were 2" or more in width.

Your expansive clays are pretty interesting and amazing. That's why most of y'all live & work on post tensioned slabs.
 
Maybe relax some of that back pressure once the elevator starts to become effective? That should keep you on the grass a bit longer and maybe help you stay in ground effect once you do lift off.
 
There is no need to use soft field takeoff technique just because you're on grass. You already said the grass is not soft. Few people ever land on fields truly soft enough to require those "soft field" techniques that get drilled into students during PPL training. Unless your tires are sinking into the ground, making deep ruts, don't worry about it being a "soft field". Just take off as normal. Yes, there will be a slightly longer takeoff roll. I think you let it get into your head, just because you're brand new to grass - combined with maybe some weak technique.

On most grass strips that are in operable condition, you don't need to treat them any differently than pavement. Though on landing at an unfamiliar grass strip where conditions are unknown, it's a good idea to do somewhat of a soft-field landing....as in just land with the nose up and hold the yoke back - not the drive it on level and let the yoke come forward immediately, as I see trike drivers do so often.
 
RoscoeT said:
There is no need to use soft field takeoff technique just because you're on grass.
Click to expand...

I don't agree.

The nosewheel is the most fragile thing on my 182 so I keep the weight off of it when operating on grass, even when taxiing.

I may not hold it completely off the ground like I would on a true soft field landing or take-off, but I always keep enough back pressure on the yoke to get the majority of the weight off of it. Again, even when taxiing. The yoke is always all the aft back when taxiing.
 
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The grass field I normally use is rarely soft, except after a heavy rain. I do use soft field techniques just to keep weight off the nose wheel. No matter now nice the field is kept, there are still grass clumps, ruts, cracks, and other uneven areas that can cause excitement.
 
Sounds like you are holding too much back pressure. Decrease the back pressure as your speed comes up and then increase again when you are ready to rotate. It's a lot harder to go wheelying down a bumpy grass field than a smooth paved runway. As long as the field isn't muddy, focus on keeping the nose wheel light, not necessarily off the ground. Don't let the plane rotate until you are at the proper speed, and then accelerate to Vx (Vx with flaps out is going to be slower than a no flaps takeoff).
 
Nice! I'd like to find some grass strips in Northern California to practice soft field operations on.
 
Ok, this is all good info.

Actually Tim, no cracks. Summer hasn't gotten brutal yet. It has been pleasant so far. I don't think we have broken 100 yet. Yesterday was hot but tolerable at altitude. Cedar Mills appears to be well maintained. Not quite golfing green but better than a golf course fairway.

I wonder if it will crack during the extreme summers. Our clay does suck. I so badly want a basement but not here. And yes, foundation repair is a HUGE business in this area.

So next go round I will reduce back pressure so I am not popping off at 50kts. I wonder if that may be part of the reason I am noticing the delay in airspeed coming up. Aerodynamic breaking due to elevator pulled to the stops.

And I am totally doing "what was drilled into me during PPL training" and maybe that was intended for muddy field ops. I think I have mistakenly associated grass with soft which may not be the case.
 
Another trick is to wait till your near rotation speed to put the flaps in, depending on how fast your flaps react.
 
1 potato 2 potato 3 potato = half flaps
6 potatoes to fully extend or retract
 
With the Skylane, I'm using 10° flaps on grass field like Cedar Mills, 20° if taller/wetter.

I wonder if using your "half flaps" would add to or detract from this equation?

Bryan, does your POH provide any guidance?
 
timwinters said:
The nosewheel is the most fragile thing on my 182 so I keep the weight off of it when operating on grass, even when taxiing.
Click to expand...

I would surely do the same, but this is more for rough field issues than soft field issues. Slightly different reasons for doing something very similar. Few encounter true soft field issues. Those who do will be making the airstrip owner very angry...unless you're the one who owns it.
 
What are you flying? I will place another vote for not starting out and holding full-aft on the TO roll.
 
No difference in process only thing it says is:
influence of runway condition

Increase by
Hard sod: 7%
Short Grass 10%
High Grass 25%
 
As mentioned there is a difference between a grass field and a rough field. Holding the elevator back is also called aerodynamic braking, so why do it on take-off? Elevator neutral and 20 degrees pops me right off. You might experiment and see what works for you.
 
Bryan, if nothing else, this experience is telling you that, if you are encountering this with just yourself in the aircraft, to be mindful of the same conditions but loaded to gross.

And let's not forget that we've yet to hit the bad Density Altitude conditions in our area
 
Alexb2000 said:
As mentioned there is a difference between a grass field and a rough field. Holding the elevator back is also called aerodynamic braking, so why do it on take-off? Elevator neutral and 20 degrees pops me right off. You might experiment and see what works for you.
Click to expand...

Can you remind us what aircraft you have? You said once, but I've forgotten.
 
skynewbie said:
Nice! I'd like to find some grass strips in Northern California to practice soft field operations on.
Click to expand...

Doesn't look like all that many public use grass fields in California. I see only 1C9 and O22. 1Q5, CA09, A28, and several way down in southern CA are dirt or gravel.
 
AggieMike88 said:
Bryan, if nothing else, this experience is telling you that, if you are encountering this with just yourself in the aircraft, to be mindful of the same conditions but loaded to gross.

And let's not forget that we've yet to hit the bad Density Altitude conditions in our area
Click to expand...

Yup. I won't fly to 3t0 w/ the kids.
Been there twice w/ the Misses and 1 bag. Once with a co worker

No plans to go there any heavier than that.
But I am going to go alone next time without the full aft for true soft field and see if I get up quicker. That field is rock hard.
 
You guys are making me want to go out there again. I always worried more about that huge tree than the grass.:)
 
Let's all go out there and cut that tree down.
 
jhausch said:
Does that have a conventional elevator or a stabilator? I ask because I think (my own personal opinion) stabilators at full up deflection from a full stop act more like a stalled wing / air brake...
Click to expand...

stabilator
 
Just figure in density alt. and factor for a longer take off roll. Good grass is fun.
 
+1 for letting it fly off.

On a 3000' short cut dry grass strip, you've got plenty. Sounds like your pulling it into the air before it wants to fly.

Turf will grab you like crack cocaine if you don't watch it. Pretty soon, you'll be cussing pavement.
 
RoscoeT said:
Few encounter true soft field issues. Those who do will be making the airstrip owner very angry...unless you're the one who owns it.
Click to expand...

But it certainly is fun when you do encounter it! There were a few times when I had more mud on my horizontal stab and bottom of the wing than I ever dreamed possible when I was still based at 0T3.

Just take the wheel pants off and go!

Just another learning experience.

But yes, as someone else mentioned, an immediate trip to the washbay is definitely in order.
 
SixPapaCharlie said:
Let's all go out there and cut that tree down.
Click to expand...

No way, muchaco... It's perfect for getting the pax to sweat a little as we barrell straight toward it on Takeoff.

Alex... let's go! We might be able to get others from the DFW board to join us.
 
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